1 /*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <stddef.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <stdint.h>
33 #include <elf.h>
34 #include <asm/page.h>
35 #include "pthread_internal.h"
36 #include "atexit.h"
37 #include "libc_init_common.h"
38
39 #include <bionic_tls.h>
40 #include <errno.h>
41
42 extern unsigned __get_sp(void);
43 extern pid_t gettid(void);
44
45 char* __progname;
46 char **environ;
47
48 /* from asm/page.h */
49 unsigned int __page_size = PAGE_SIZE;
50 unsigned int __page_shift = PAGE_SHIFT;
51
52
53 int __system_properties_init(void);
54
__libc_init_common(uintptr_t * elfdata)55 void __libc_init_common(uintptr_t *elfdata)
56 {
57 int argc = *elfdata;
58 char** argv = (char**)(elfdata + 1);
59 char** envp = argv + argc + 1;
60
61 pthread_attr_t thread_attr;
62 static pthread_internal_t thread;
63 static void* tls_area[BIONIC_TLS_SLOTS];
64
65 /* setup pthread runtime and maint thread descriptor */
66 unsigned stacktop = (__get_sp() & ~(PAGE_SIZE - 1)) + PAGE_SIZE;
67 unsigned stacksize = 128 * 1024;
68 unsigned stackbottom = stacktop - stacksize;
69
70 pthread_attr_init(&thread_attr);
71 pthread_attr_setstack(&thread_attr, (void*)stackbottom, stacksize);
72 _init_thread(&thread, gettid(), &thread_attr, (void*)stackbottom);
73 __init_tls(tls_area, &thread);
74
75 /* clear errno - requires TLS area */
76 errno = 0;
77
78 /* set program name */
79 __progname = argv[0] ? argv[0] : "<unknown>";
80
81 /* setup environment pointer */
82 environ = envp;
83
84 /* setup system properties - requires environment */
85 __system_properties_init();
86 }
87
88 /* This function will be called during normal program termination
89 * to run the destructors that are listed in the .fini_array section
90 * of the executable, if any.
91 *
92 * 'fini_array' points to a list of function addresses. The first
93 * entry in the list has value -1, the last one has value 0.
94 */
__libc_fini(void * array)95 void __libc_fini(void* array)
96 {
97 int count;
98 void** fini_array = array;
99 const size_t minus1 = ~(size_t)0; /* ensure proper sign extension */
100
101 /* Sanity check - first entry must be -1 */
102 if (array == NULL || (size_t)fini_array[0] != minus1) {
103 return;
104 }
105
106 /* skip over it */
107 fini_array += 1;
108
109 /* Count the number of destructors. */
110 for (count = 0; fini_array[count] != NULL; count++);
111
112 /* Now call each destructor in reverse order. */
113 while (count > 0) {
114 void (*func)() = (void (*)) fini_array[--count];
115
116 /* Sanity check, any -1 in the list is ignored */
117 if ((size_t)func == minus1)
118 continue;
119
120 func();
121 }
122 }
123